Package org.deeplearning4j.graph.api

Interface IGraph<V,​E>

  • All Known Implementing Classes:
    BaseGraph, Graph
    public interface IGraph<V,​E>

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      void addEdge​(int from, int to, E value, boolean directed)
      Convenience method for adding an edge (directed or undirected) to graph
      void addEdge​(Edge<E> edge)
      Add an edge to the graph.
      int[] getConnectedVertexIndices​(int vertex)
      Return an array of indexes of vertices that the specified vertex is connected to.
      Specifically, for undirected graphs return int[] of all X.vertexID() such that (vertex -- X) exists
      For directed graphs, return int[] of all X.vertexID() such that (vertex -> X) exists
      List<Vertex<V>> getConnectedVertices​(int vertex)
      Get a list of all of the vertices that the specified vertex is connected to
      Specifically, for undirected graphs return list of all X such that (vertex -- X) exists
      For directed graphs, return list of all X such that (vertex -> X) exists
      List<Edge<E>> getEdgesOut​(int vertex)
      Returns a list of edges for a vertex with a given index For undirected graphs, returns all edges incident on the vertex For directed graphs, only returns outward directed edges
      Vertex<V> getRandomConnectedVertex​(int vertex, Random rng)
      Randomly sample a vertex connected to a given vertex.
      Vertex<V> getVertex​(int idx)
      Get a vertex in the graph for a given index
      int getVertexDegree​(int vertex)
      Returns the degree of the vertex.
      For undirected graphs, this is just the degree.
      For directed graphs, this returns the outdegree
      List<Vertex<V>> getVertices​(int[] indexes)
      Get multiple vertices in the graph
      List<Vertex<V>> getVertices​(int from, int to)
      Get multiple vertices in the graph, with secified indices
      int numVertices()
      Number of vertices in the graph

    • Method Detail

      • numVertices

        int numVertices()
        Number of vertices in the graph

      • getVertex

        Vertex<V> getVertex​(int idx)
        Get a vertex in the graph for a given index
        Parameters:
        idx - integer index of the vertex to get. must be in range 0 to numVertices()
        Returns:
        vertex

      • getVertices

        List<Vertex<V>> getVertices​(int[] indexes)
        Get multiple vertices in the graph
        Parameters:
        indexes - the indexes of the vertices to retrieve
        Returns:
        list of vertices

      • getVertices

        List<Vertex<V>> getVertices​(int from,
                            int to)
        Get multiple vertices in the graph, with secified indices
        Parameters:
        from - first vertex to get, inclusive
        to - last vertex to get, inclusive
        Returns:
        list of vertices

      • addEdge

        void addEdge​(Edge<E> edge)
        Add an edge to the graph.

      • addEdge

        void addEdge​(int from,
             int to,
             E value,
             boolean directed)
        Convenience method for adding an edge (directed or undirected) to graph

      • getEdgesOut

        List<Edge<E>> getEdgesOut​(int vertex)
        Returns a list of edges for a vertex with a given index For undirected graphs, returns all edges incident on the vertex For directed graphs, only returns outward directed edges
        Parameters:
        vertex - index of the vertex to
        Returns:
        list of edges for this vertex

      • getVertexDegree

        int getVertexDegree​(int vertex)
        Returns the degree of the vertex.
        For undirected graphs, this is just the degree.
        For directed graphs, this returns the outdegree
        Parameters:
        vertex - vertex to get degree for
        Returns:
        vertex degree

      • getRandomConnectedVertex

        Vertex<V> getRandomConnectedVertex​(int vertex,
                                   Random rng)
                            throws NoEdgesException
        Randomly sample a vertex connected to a given vertex. Sampling is done uniformly at random. Specifically, returns a random X such that either a directed edge (vertex -> X) exists, or an undirected edge (vertex -- X) exists
        Can be used for example to implement a random walk on the graph (specifically: a unweighted random walk)
        Parameters:
        vertex - vertex to randomly sample from
        rng - Random number generator to use
        Returns:
        A vertex connected to the specified vertex,
        Throws:
        NoEdgesException - thrown if the specified vertex has no edges, or no outgoing edges (in the case of a directed graph).

      • getConnectedVertices

        List<Vertex<V>> getConnectedVertices​(int vertex)
        Get a list of all of the vertices that the specified vertex is connected to
        Specifically, for undirected graphs return list of all X such that (vertex -- X) exists
        For directed graphs, return list of all X such that (vertex -> X) exists
        Parameters:
        vertex - Index of the vertex
        Returns:
        list of vertices that the specified vertex is connected to

      • getConnectedVertexIndices

        int[] getConnectedVertexIndices​(int vertex)
        Return an array of indexes of vertices that the specified vertex is connected to.
        Specifically, for undirected graphs return int[] of all X.vertexID() such that (vertex -- X) exists
        For directed graphs, return int[] of all X.vertexID() such that (vertex -> X) exists
        Parameters:
        vertex - index of the vertex
        Returns:
        list of vertices that the specified vertex is connected to
        See Also:
        getConnectedVertices(int)